摘要
随机水文地质学方法,较传统的确定性方法而言,是解决非均质含水层中水流和溶质运移问题的一种更为合理的手段。据以往研究,假设渗透系数场遵循对数正态分布,利用直接傅立叶变换方法来生成渗透系数随机场。应用基于随机理论的蒙特卡罗方法,来研究渗透系数的空间变异性对污染物运移结果的影响。实例研究表明,污染物在含水层中运移过程中污染羽的展布范围(二阶矩)随着渗透系数空间变异方差的增大而扩大,而污染羽在空间上的质心位置(一阶矩)基本不受方差的影响,仅取决于渗透系数随机场的均值大小。另外还分析了污染羽在各点的浓度变化方差和变异系数分别随渗透系数变异方差的变化状况。
Compared with commonly used deterministic methods, the stochastic hydrogeology method is a more rational resort for solving the flow and transport problems in the heterogeneous aquifers. On the assumption that the hydraulic conductivity field follows a lognormal distribution, the direct Fourier transform is introduced to generate muhiple realizations of hydraulic eond, ctivity field. Then the Monte Carlo method, based on the stochastic theory, is applied to investigate the effect of the spatial variation of hydraulic conductivity on the fate of contaminant plume. For the contaminant plume examined in this synthetic example study the spatial second moments defining the spread of the contaminant plume around its centroid increase with the enlargement of the variance of hydraulic conductivity distribution, while the first moment specifying the centroid of the plume is not influenced by the variance of hydraulic conductivity but dominated by the mean of hydraulic conductivity. Additional analysis demonstrates the sensitivity of both variance and coefficient of variation of plume concentration to the various variances of hydraulic conductivity field.
出处
《水科学进展》
EI
CAS
CSCD
北大核心
2006年第1期29-36,共8页
Advances in Water Science
基金
国家自然科学基金资助项目(4000202240472130)~~
关键词
非均质
渗透系数
空间变异性
污染物运移
污染羽评估
随机模拟
heterogeneity
hydraulic conductivity
spatial variation/variability
transport of contaminant
contaminant plume estimation
stochastic modeling
